MyD88-dependent influx of monocytes and neutrophils impairs lymph node B cell responses to chikungunya virus infection via Irf5, Nos2 and Nox2

McCarthy, Mary K.; Reynoso, Glennys V.; Winkler, Emma S.; Mack, Matthias; Diamond, Michael S.; Hickman, Heather D.; Morrison, Thomas E.

Draining lymphoid organs have a critical role in the initiation of effective adaptive immune responses to vaccines and pathogens. B cells and virus-specific antibodies (Abs) are important arms of the adaptive immune response for limiting viral dissemination and controlling viral infections. The antiviral Ab response is initiated in the draining lymph node (dLN) through a series of molecular interactions and cellular movements that require intact lymphoid tissue architecture and function. Naïve B cells enter the dLN through high endothelial venules (HEVs) and then migrate to defined follicles subjacent to the dLN subcapsular sinus (SCS) [1] . B cells acquire viral antigen through interactions with SCS macrophages which readily acquire viral antigens borne by the afferent lymphatics [2] . After activation, B cells migrate to the borders of the B cell follicle and to the interfollicular region of the dLN to encounter CD4 + T cells. Some of these activated, proliferating B cells go on to form plasmablasts, while others persist in tight clusters in the follicle, forming germinal centers (GCs) [3, 4] .